The patient was 29 years old. He had no pain, no swelling and no recollection of dental trauma. Yet an X-ray revealed a large area of bone destruction around two upper front teeth.
One of the teeth had received root canal treatment five years earlier. The neighbouring tooth had never been treated, but testing showed that its pulp was necrotic. Both teeth were associated with asymptomatic apical periodontitis.
A CBCT scan revealed the true extent of the problem: the lesion measured approximately 15 mm by 10 mm and had affected the outer bone plate and part of the incisive canal.
It looked serious, even though the patient felt nothing.
Three possible treatment paths
The clinical team discussed three approaches with the patient:
- Treat the untreated tooth first and monitor the healing.
- Perform root canal treatment followed by endodontic microsurgery.
- Extract the affected teeth and plan an implant-supported replacement.
The patient selected the most conservative option.
The necrotic lateral incisor was treated under rubber-dam isolation and magnification. The root canal was carefully cleaned, disinfected and sealed. Rather than immediately operating on the area or extracting both teeth, the clinicians allowed the tissues time to respond.
What happened during healing
At the one-year follow-up, the patient remained free of symptoms. More importantly, the new CBCT scan showed substantial healing and reformation of the previously damaged outer bone.
One area had not healed completely: the region around the front tooth that had received root canal treatment five years earlier.
The clinicians then retreated that tooth non-surgically, addressing the remaining source of infection inside its canal system.
At the two-year follow-up, both conventional radiographs and CBCT imaging showed complete healing of the lesion.
Why the absence of pain can be misleading
Dental infections do not always produce obvious symptoms. A tooth may stop hurting after its pulp dies, while infection continues to develop around the end of the root.
That is why diagnosis cannot be based on pain alone. Pulp testing, clinical examination and appropriate imaging can reveal problems that would otherwise remain unnoticed.
This case also shows that bone healing is gradual. The first treatment produced major improvement, but careful follow-up identified one remaining problem. The plan was adjusted rather than being declared a success too early.
Conservative does not mean passive
Choosing a non-surgical approach did not mean ignoring the size of the lesion. It involved precise disinfection, controlled treatment and radiographic monitoring over time.
Not every large lesion can be managed this way. Persistent infection, an independent cystic lesion, a root fracture or an unrestorable tooth may still require surgery or extraction. Imaging alone also cannot always determine the exact biological nature of a lesion.
The lesson from this case is not that surgery is unnecessary. It is that the source of infection should be identified and the most conservative reasonable treatment considered before a tooth is removed.
Sometimes the bone has a remarkable capacity to recover—once the infection preventing it from healing has been properly controlled.
Published case reviewed: Alyousef and Almohaimeed, “Healing of a Large Periapical Lesion Using Non-Surgical Root Canal Retreatment,” Cureus, 2024. This case does not guarantee the same result in other clinical situations.
